Nanotube fibers stand strong – but for how long?

Rice scientists calculate how carbon nanotubes and their fibers experience fatigue

Up here in the macro world, we all feel fatigue now and then. It’s the same for bundles of carbon nanotubes, no matter how perfect their individual components are.

A Rice University study calculates how strains and stresses affect both “perfect” nanotubes and those assembled into fibers and found that while fibers under cyclic loads can fail over time, the tubes themselves may remain perfect. How long the tubes or their fibers sustain their mechanical environment can determine their practicality for applications.

That made the study, which appears in Science Advances, important to Rice materials theorist Boris Yakobson,graduate student Nitant Gupta and assistant research professor Evgeni Penev of Rice’s George R. Brown School of Engineering. They quantified the effects of cyclic stress on nanotubes using state-of-the-art simulation techniques like a kinetic Monte Carlo method. They hope to give researchers and industry a way to predict how long nanotube fibers or other assemblies can be expected to last under given conditions.

– See more at Rice News

Nickel’s need for speed makes unusual nanoribbons

Rice lab studies mechanism behind bilayer molybdenum disulfide ribbons

It’s now possible to quickly make ultrathin nanoribbons of molybdenum disulfide, with a speedy nickel nanoparticle leading the way.Materials theorist Boris Yakobson and his team at Rice University’s George R. Brown School of Engineering collaborated with the Honda Research Institute and others to make tightly controlled bilayer nanoribbons of the material commonly known as MoS2, a step forward with potential applications in quantum computing.

Honda, with scientists at Rice, Columbia University and Oak Ridge National Laboratory, found that nanoparticles of nickel exposed to molybdenum oxide and sodium bromide powders and sulfur gas in a chemical vapor deposition furnace wrangle the resulting nanoribbons into shape, constraining their width to several micrometers. At the same time, the nickel catalyzes a thinner second layer of less than 30 nanometers, roughly equivalent to the width of the nanoparticle itself.

The study appears in Science Advances.

– See more at Rice News